Turret indexing means

ABSTRACT

A reliable, rapid turret indexing means having particularly desirable decelerative characteristics, which means is easily combined with simple turret engagement and disengagement movements, and which means is especially adapted for transferring radially disposed core rods between work stations in an injection blow molding machine. This indexing means comprises a crank arm pivotally mounted for movement about the turret axis between first and second limit positions and connected to the driving end of a linear link member the other end of which is driven through a linear path parallel to the crank arm at the second of its limit positions. A driving means, preferably a hydraulic cylinder, is also provided to exert compressive force on the linear link member to propel the crank arm from its first limit position toward its second limit position and to return the crank arm to its first position.

United States Patent Wheaton, III et al.

Dec. 19,1972

TURRET INDEXING MEANS [52] US. Cl. ..425/324 B, 425/342, 425/348 [51]Int. Cl. ..B29d 23/03 [58 Field of Search ..l8/5 BB, 5 B], 2 D, 2 B, 2C,

18/2 0', 2 H; 425/324 B, 342, 34s

Primary ExaminerH. A. Kilby, Jr. Attorney-Paul & Paul [5 7] ABSTRACT Areliable, rapid turret indexing means having particularly desirabledecelerative characteristics, which means is easily combined with simpleturret engagement and disengagement movements, and which means isespecially adapted for transferring radially disposed core rods betweenwork stations in an injection blow molding machine. This indexing meanscomprises a crank arm pivotally mounted for movement about the turretaxis between first and second limit positions and connected to thedriving end of a linear link member the other end of which is driventhrough a linear path parallel to the crank arm at the second of 1References cued its limit positions. A dl'lVll'lg means, preferably aUNITED STATES PATENTS hydraulic cylinder, is also provided to exertcompressive force on the linear lmk member to propel the 3,100,9138/1963 DeMatteo ..l8/5 B] X crank arm f its first limit position towardits 2853736 9/1958 Gussonh" 18/5 UX second limit'position and to returnthe crank arm to 3,070,843 1/1963 Jurgeleit... 1 8/20 H 7 its firstposition 3,584,337 l/l97l Aoki ..l8/5 B] 1 1 Claims, 8 Drawing Figures3o 24\\ t T- /,i- S, r L, 1 I IL. l L. 1 IF PATENTED DEC 19 m2 SHEET 10F 5 INVENTORS. Theodore C. Wheoron 111 BY Walter Ponus ATTORNEYSPKTENTED Etc 19 I972 SHEET 2 [IF 5 PATENTED DEC 19 m2 3 7 06 51 7 sum 3OF 5 hllh PATENTED mm s 1912 SHEET 5 OF 5 TURRET INDEXING MEANSINTRODUCTION AND BACKGROUND This invention relates to a turret indexingmeans characterized by relatively short total stroke time and rapid butcontrolled decelerative movement at the end of the indexing motion. Inparticular this invention relates to a turret indexing means used totransfer core rods between various radially disposed stations ininjection blow molding machines.

As is well known, numerous machine designs involve the transfer of workpieces between various radially disposed work stations by means ofturret upon which said work pieces are mounted. Mechanisms for moving orindexing such turrets through a fraction of a revolution about theturret axis for purposes of transferring work pieces between workstations are generally referred to herein as turret indexing means ormechanisms.

In many types of mass production apparatus utilizing turret mechanisms,productivity can be increased by reducing the total time required forthe turret indexing stroke or movement. In certain specific applicationsthere may be other reasons for increasing the speed of the turretindexing movement. This is particularly true in an injection blowmolding machine wherein fast indexing may be desirable in order tomaintain optimum melt characteristics of a parison formed at one workstation of the machine while transferring it to a sub-' sequent workstation where the parison is blown into a hollow product.

Simply increasing the speed of an indexing mechanism often introducescertain difficulties however. Most notably, as the speed with which theturret and its associated apparatus is rotated about the turret axisincreases, so, obviously, does its inertia. Bringing it to a stop at theconclusion of the indexing movement requires a great deal of energyabsorption by mechanical members which must nevertheless ensure that theturret comes to rest at a precisely predetermined angular position.Stops in such mechanisms are often characterized by jolts or rapid,uncontrolled deceleration. Such mechanisms are therefore usuallyexpensive, difficult to maintain and prone to mechanical failure.

This problem is aggravated as machine size and complexity increase bythe resultant increased mass of the turret and its associated apparatusand by the relatively greater precision often required in such machines.

With a view to this problem, therefore, it is an object of the presentinvention to provide a turret indexing mechanism which is relativelysimple, fast, and precise and which is characterized by a desirabledecelerative movement at the end of the indexing movement.

A further object of this invention is to provide such a turret indexingmeans adapted to engage and to disengage intermittently a turret, suchas that used in certain types of injection blow molding machines.

Still another object of this invention is to provide such a turretindexing mechanism which prevents damage due to attempted turretengagement when the cooperating engaging means are not aligned.

BRIEF DESCRIPTION OF THE INVENTION These and other objects, which willbecome apparent in the course of the following discussion, are met by aturret indexing means having a crank arm, the inner end of which ispivotally mounted on the turret axis for movement between first andsecond limit positions angularly displaced less than 180, preferably60-120, from one another. The outer end of the crank arm is pivotallyconnected to the driving end of a linear link member. This linear linkmember also has a driven end reciprocably movable in a linear path. Thecrank arm at its second limit position is parallel to this linear pathand perpendicular to the linear link member. The thrust on the drivenend of the linear link member is thus transposed decreasingly lesseffectively into radial movement of the crank arm as the crank armapproaches its second limit position. This provides rapid movement witha timely and significant decelerative phase at the conclusion thereof.

Preferably, this indexing mechanism is used in an injection blow moldingmachine having three or four work stations each radially disposed withequal angular displacement from adjacent stations. Prior to eachindexing movement, the turret moves along its axis toward and intoengagement with the indexing mechanism. After indexing, through eitheror as the case may be, to the second limit position of the crank arm,the turret disengages and returns to its original position while theindexing means does likewise.

The actual means for engaging the turret and indexing means preferablycomprises a radially disposed flag member movable circumferentially inunison with the indexing mechanism crank arm and mating slots on theturret for receiving this flag member. These slots are angularlydisplaced from one another by an angle corresponding to that between thefirst and second limit positions of the crank arm.

The flag member is preferably mounted for pivotal movement about an axisperpendicular to its planar faces. This permits the flag member to beautomatically rotated out of its engagement position if engagement isattempted when the flag is not aligned with one of the mating slots andprevents damage to the apparatus.

DETAILED DESCRIPTION OF THE DRAWINGS AND PREFERRED EMBODIMENT OF THEPRESENT INVENTION For a better understanding of the present invention,reference is made to the appended claims and to the following detaileddiscussion, taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a front view of an injection blow mold machine utilizing theturret indexing mechanism of the present invention;

FIG. 2 is a plan view of the turret and work stations in the machine ofFIG. 1;

FIG. 3 is an expanded, sectional, plan view of the machine shown inFIGS. 1 and 2, taken in the plane 3- 3, showing specifically and indetail the preferred embodiment of the turret indexing means of thepresent invention;

FIGS. 4 and 5 are sectional views of the turret indexing means shown inFIG. 3, taken in the planes 4-4 and 5-5, respectively;

FIG. 6 is a sectional detail view of one part of the turret indexingmeans shown in FIG. 3, taken in the plane 6-6;

FIG. 7 is an enlarged side view of the turret indexing meansengagementmechanism of the apparatus previously illustrated; and

FIG. 8'is a sectional view, in the plane 8-8 of mechanism shown indetail in FIG. 7.

Referring specifically now to FIG. 1, there is shown a plate framestructure 10 having an opening 12 therein. On the lower horizontalsurface of opening 12 is mounted stationary mold half base 14. Directlyabove base 14 is movable blow mold half mounting member 16 and movableinjection mold half mounting member 18, each attached respectivelythrough connecting means 20 and 22 to yoke member 24 movable verticallyby hydraulic piston 26 counterbalanced by constant pressure pneumaticcylinders 28, all of which, except the lower portions of connectingmeans 20 and 22 and movable mold half mounting members 16 and 18attached thereto, are enclosed within plate frame structure 10.

Connecting means 20 and 22 and hydraulic piston 26 are all attached bypivotal connections 30 to yoke the member 24 in order to provide for anyslight vertical movement of connecting means 20 and 22 and piston 26relative to one another.

Between stationary mold half base 14 and movable mold half mountingmembers 16 and 18 are disposed mold positioning members 32, guide bars34, stationary blow mold half 36, movable blow mold half 38, stationaryinjection mold half 40 and movable injection mold half 42.

Connecting members 46 and 48 are associated with an injection moldlocking system described in more detail with reference to FIG. 2.

Other, more conventional, mold opening, closing and clamping mechanismsmay also be incorporated in the injection blow molding machine ofFIG. 1. For example, separate hydraulic cylinders mounted on thevertical center lines of the injection and blow molds could be used toopen, to close and to apply the necessary clamping force to each ofthese molds.

Also seen in FIG. 1 is turret base 50, with turret positioning pins (notillustrated) thereon, and turret head 52 with four equi-angularlydisplaced sets of mandrels or core rods 54a-d (a and b not shown inFIG. 1) radially disposed therefrom. (Typically each such set maycomprise from 1 to individual core rods or mandrels with the blow moldsand injection molds each having a corresponding number of cavities.)

Although not illustrated, the turret head may also have three, ratherthan four, equi-angularly displaced, radially projecting sets of corerods. In that case, the machine would have one rather than two idle workstations, i.e. stations where core rods are not enclosed by molds forone of the molding operations. Also, the work stations would bedisplaced 120, rather than 90, from adjacent work stations. Still othertypes of machines may have from three to six such work stations.

Turret head 52 is biased upwardly by a constant pressure piston (notshown) in plate frame structure 10 and moved downwardly by lever arm 58with bearing surface 60 riding on bearing member 62 which is connectedthrough shaft 64 to turret head 52. Lever arm 58 is pivotally mounted atone end 66 to plate frame structure 10 and at the other end 68 to anappendage 70 movable with movable blow mold half connecting means 20. Asafety switch 72 signals when an overload occurs in the core rodlowering system.

Indexing of turret head 52 is accomplished when turret head 52 movesupward, and one of the slots 74a-d is engaged by flag member 76 attachedto a lower crank arm 78 of the indexing mechanism 80, of the presentinvention, which is actuated by actuator 82, all of which is shown anddescribed in more detail hereinafter. The convenience of engaging anddisengaging turret head 52 and the indexing means of this invention,simply by the reciprocation of turret head 52 between two axiallydisplaced limit positions, is an important feature of the presentinvention.

Turning now to FIG. 2, which is a sectional plan view of the machineshown in FIG. 1 and inwhich like elements are numbered accordingly,there is seen hydraulic cylinder 44, which, acting through connectingmembers 46 and 48, imparts a slight rotational movement to a firstinterrupted spline member 45 after injection mold 40, 42 has beenclosed, thereby mating the inward projections 45a thereof withcorresponding inward projections 47a of second interrupted spline member(not shown) associated with movable mold connecting means'22 and locatedbelow first interrupted spline member 45 when connecting means 22 andmovable mold half 42 are in their lowered position. The function ofthese mating interrupted spline members is to transmit a resistanceforce, to an additional injection mold clamping force, through member 45to frame structure 10. This additional injection mold clamping force,which is applied independently of piston 26 and yoke member 24, isimparted to movable injection mold half 42 by a separate hydraulicpiston and cylinder combination, not shown, which is included in andintegral with movable mold connecting means 22.

Further shown in FIG. 2 is a portion of a conventional plastificationand injection means 84 terminating in melt manifold 86 having individualnozzles 88 mating with and feeding individual cavities in injection mold40, 42. Conventional plastification and injection means 84 may comprise,for example, a feed hopper, a heated barrel, and ,a longitudinallymovable extruder screw therein, the barrel terminating in a primarynozzle mating in a suitable recess of manifold 86.

Also seen in FIG. 2 is an ejector mechanism 90 for removing blownbottles from core rod set 54c.

Seen more clearly in FIG. 2 is lower crank arm 78, with flag member 76,and slots 74a, b, and d on turret head 52 for engaging flag member 76.Radial arm 78 is fixedly attached to indexing shaft 92 of indexingmechanism 80, freely movable through the center of which is turret headraising shaft 64.

Looking now to FIGS. 3-5, wherein the preferred embodiment of theindexing mechanism of this invention is shown in more detail, there isseen index mechanism housing 94 with internal support members 96 havingguide slots 98 therein. Movable longitudinally in guide slots 98 arebearing members 100 connected by axle 102 retained by nuts 104, to oneend (the driven end) of linear link member 106, which is also pivotallyconnected by axle 102 through adjustable sleeve 108 to a connecting rod110 of a hydraulic piston housed in cylindrical housing 112.

At its opposite end (the driving end), linear link member 106 ispivotally connected by axle 114 and retainers 116 to an arcuatelymovable end 118 of upper crank arm 120 extending from hollow indexmechanism shaft 92. As shown, upper crank arm 120 is in its first limitposition, which is one terminus of a 90 indexing stroke.

Shown by phantom lines in FIGS. 3 and 4 is the second limit position ofupper crank arm 120 and linear link member 106 at their second terminus.In this second limit position, the linear link member 106 issubstantially perpendicular to upper crank arm 120, which is alsosubstantially parallel to the linear path through which the driven endof linear link member 106 is driven.

Generally, the first limit position must be angularly displaced lessthan 180 from the second limit position. Preferably, however, thisangular displacement is less than 120 and most preferably it is either90 for a four station machine or 120 for a three station machine.

Preferably also, linear link member 106 is approximately the same lengthas crank arm 120. This relationship results in a compact mechanism whichnevertheless provide an effective force transfer with all of thecharacteristics inherent in the present invention.

In all cases, a compressive force is exerted on linear link member 106to move upper crank arm 120 from its first limit position and toward itssecond limit position. In the preferred form of the present invention,this compressive force is provided by the hydraulic piston in housing112, which also, by reverse actuation, returns the indexing mechanism toits starting position after the indexing stroke has been completed andturret head 52 disengaged. Inherently, this hydraulic actuation means issimple, reliable, fast and is characterized by smooth but rapidacceleration in the initial phase of its movement, thus avoiding undueloading of the apparatus due to the inertia of the turret head 52 atrest.

Indexing mechanism 80 is lubricated by lubricating fluid substantiallyfilling housing 94. As seen in FIG. 5, seals 134 retain this lubricatingfluid while permitting free radial movement of shaft 92 on rollerbearings 136.

In FIG. 6, which is a sectional detail view of the adjustable sleeve 108in the plane 6-6, there is shown the threaded projecting end 122 ofconnecting rod 110 with mating threaded connecting member 124 having aslot 126 and a tightening bolt 128. The longitudinal position ofconnecting rod 110 relative to connecting member 124 and linear linkmember 106 is adjustable through access hole 132 by means of a screwdriver in slot 130 provided therefor after removal of tightening bolt128 through an access hole (not shown) in the top of index mechanismhousing 94.

In FIG. 7, which is an expanded side view of the outer end of lowercrank arm 78 and flag member 76 an a part of turret head 52, partiallycut away to show flag receiving slot 74c, it will be seen that flagmember 76 is mounted to permit pivotal movement about an axis 138perpendicular to its planar faces. As seen in FIG. 8, which is asectional view in the plane 8-8 of FIG. 7, flag member 76 is retained inthe position shown in FIG. 7 by ball detent and spring loaded ballmechanism 140. Wear plates 142 are provided to prevent frictional weardue to the rotation of flag member 76 in crank arm 78.

Rotation of flag member 76;, into the position shown by phantom lines inFIG. 7, may be accomplished manually, using handle 142 provided for thatpurpose, or automatically by the striking of flag member 76 on a portionof turret head 52 other than slots 74a-d. The latter is a safetyfeature, preventing damage to the apparatus in the event of attemptedengagement when flag member 76 is not aligned with one of the slots74a-d. i

The ability to rotate flag member 76 manually is important because inits rotated position, flag member 76 does not engage turret head 52.This facilitates machine set up by permitting turret head 52 to beindexed manually, thus ensuring proper clearances, etc.

A stop 144 is provided to limit the rotational movement of flag member76.

From the foregoing discussion, it is evident that the indexing mechanismof the present invention may be utilized in conjunction with a widevariety of apparatus having turret elements, Any of numerous types ofengagement and disengagement means may be used for unidirectional turretindexing, although a particularly convenient and useful feature of thisinvention, as shown and discussed above, is its suitability forengagement and disengagement by simple axial movement of the turret tobe indexed.

With regard specifically to the operation of the apparatus illustratedin FIGS. l-8, starting with the molds in their closed position, plasticmaterial is injected by plastiflcation and injection means 84 intoinjection mold cavities, defined by injection mold halves 40, 42,forming parisons or bottle preforms about the mandrels or core rods ofset 54a. The molds are then opened by actuation of hydraulic piston 26moving yoke member 24 and mold mounting members 16 and 18 in unison.

Turret head 52 is simultaneously raised one half the distance of theupward movement of the movable mold halves, the upward movement of leverarm 58 in unison with the mold opening mechanism actuated by hydraulicpiston 26 permitting it to do so. Slot 74a is thereby engaged with flag76, and indexed through 90 by indexing means actuated from the positionshown in FIGS. 4 and 5 by the piston attached to connecting rod 110. Themolds and turret head 52 are then lowered (and the molds closed) byreversal of the mold opening movement previously described.Simultaneously indexing means 80 is disengaged and is returned to itsstarting position in readiness for the next indexing stroke. A secondset of parisons are then formed on the next adjacent core rod set 54dwhile the parisons formed in the preceding cycle are blow formed intohollow bottles in blow mold cavities, defined by blow mold halves 36,38, by the introduction of high pressure fluid, such as compressed air,through the core rods of set 54a. The mold is then opened and the cyclerepeated with the blown bottles formed in the preceding cycle removed byejector mechanism while the second set of parisons is blown in the blowmold cavities and still another set of parisons are formed in theinjection mold cavities. The cycle is then repeated indefinitely.

As will be understood by those skilled in the art, while the presentinvention has been described only with reference to its preferredembodiment, it is not limited thereto. Rather, numerous otherembodiments and applications will be apparent to those skilled in theart and the appended claims are intended to cover all such modifiedforms of this invention which are within its true spirit and scope.

With regard to the injection blow machine shown What is claimed is: 10

1. Injection blow molding machine including a turret indexing means,said turret indexing means comprising:

a. a crank arm pivotally mounted at its inner end on the axis of saidturret for movement about said axis between first and second angularlydisplaced limit positions less than 180 apart;

b. a linear link member having a driven end movable in a linear pathapproximately parallel 'to said crank arm at said second limit positionand a driving end pivotally connected to the outer end of said crankarm, said linear link member and said crank arm being approximatelyperpendicular to one another at said second limit position, and

c. driving means (1) for applying compressive force on said linear linkmember at the driven end thereof to move said crank arm away from saidfirst limit position and toward said second limit position and (2) forreturning said crank arm to said first position; said injection blowmolding machine comprising:

d. a turret with axial movement means to move said turretreciprocatively along its axis between first and second limit positionsthereof, and at least three equiangularly displaced radially projectingsets of at least one core rod and means for selectively introducingfluid under pressure into the space surrounding at least one of saidcore rod sets,

e. injection and blow molds, each consisting of stationery and movablemold halves with means to open and close said molds by movement of saidmovable mold halves in a direction parallel to, but of substantiallygreater distance than, said turret axial movement, said molds in theirclosed positions enclosing, respectively, adjacent core rod sets whensaid turret is at the first of its axial movement limit positions,

f. means for injecting a plastic material into said injection mold whenit is in its closed position,

g. said turret indexing means further including means for engaging saidturret and said turret indexing means when said molds are in their openposition and said turret is at the second of its axial movement limitpositions, and

h. means for removing blown products from one of 55 said core rod setsnot enclosed by said injection and blow molds while said molds are intheir closed position.

2. Injection blow molding machine, as recited in claim 1, wherein saidfirst limit position of said crank arm is displaced up to 120 from saidsecond limit position.

3. Injection blow molding machine, as recited in claim 1, wherein saidfirst limit position of said crank arm is displaced 120 from said secondlimit position.

4. In ection blow molding machine, as recited m claim 1, wherein saidfirst limit position of said crank arm is displaced from said secondlimit position.

5. Injection blow molding machine, as recited in claim 1, wherein saiddriving means comprises a hydraulic piston.

6. Injection blow molding machine, as recited in claim 1, wherein saidcrankvarm rotates about said turret axis in unison with a second crankarm having at its outer end a first engagement means for engaging saidturret.

7. Injection blow molding machine, as recited in claim 6, wherein saidfirst engagement means comprises a radially disposed flag member andsaid second engagement means comprises a plurality of receiving slotsfor said flag member, said slots having an angular displacementtherebetween corresponding to the angle between said limit positions ofsaid crank arm.

8. Injection blow molding machine, as recited in claim 7, wherein saidflag member is pivotally mounted on said second crank arm to permitrotation of said flag member about an axis perpendicular to the planarfaces thereof into a position wherein it does not engage said secondengagement means.

9. Injection blow molding machine, as recited in claim 8, wherein saiddriving means comprises a hydraulic piston, and said crank arm limitpositions are displaced 90-120.

10. Injection blow molding machine, as recited in claim 9, wherein saidcrank arm and said linear link member are of approximately equal length.

11. Injection blow molding machine, as recited in claim 9, furtherincluding sequencing means for repeatedly producing the followingsequence of events,

a. turret moves toward and engages said indexing means, while movablemold halves move in unison therewith to open said injection and blowmolds,

b. driving means moves said crank arm to said second limit position,

c. turret moves away from and disengages said indexing means, whilemovable mold halves move in unison therewith to close said injection andblow molds,

. indexing means returns crank arm to said first limit position,

e. plastic is injected into said injection molds, compressed fluid isreleased into the space surrounding said core rod set enclosed by saidblow molds, and bottles are removed from one of said core rod sets notenclosed by said injection and blow molds.

1. Injection blow molding machine including a turret indexing means,said turret indexing means comprising: a. a crank arm pivotally mountedat its inner end on the axis of said turret for movement about said axisbetween first and second angularly displaced limit positions less than180* apart; b. a linear link member having a driven end movable in alinear path approximately parallel to said crank arm at said secondlimit position and a driving end pivotally connected to the outer end ofsaid crank arm, said linear link member and said crank arm beingapproximately perpendicular to one another at said second limitposition, and c. driving means (1) for applying compressive force onsaid linear link member at the driven end thereof to move said crank armaway from said first limit position and toward said second limitposition and (2) for returning said crank arm to said first position;said injection blow molding machine comprising: d. a turret with axialmovement means to move said turret reciprocatively along its axisbetween first and second limit positions thereof, and at least threeequiangularly displaced radially projecting sets of at least one corerod and means for selectively introducing fluid under pressure into thespace surrounding at least one of said core rod sets, e. injection andblow molds, each consisting of stationery and movable mold halves withmeans to open and close said molds by movement of said movable moldhalves in a direction parallel to, but of substantially greater distancethan, said turret axial movement, said molds in their closed positionsenclosing, respectively, adjacent core rod sets when said turret is atthe first of its axial movement limit positions, f. means for injectinga plastic material into said injection mold when it is in its closedposition, g. said turret indexing means further including means forengaging said turret and said turret indexing means when said molds arein their open position and said turret is at the second of its axialmovement limit positions, and h. means for removing blown products fromone of said core rod sets not enclosed by said injection and blow moldswhile said molds are in their closed position.
 2. Injection blow moldingmachine, as recited in claim 1, wherein said first limit position ofsaid crank arm is displaced up to 120* from said second limit position.3. Injection blow molding machine, as recited in claim 1, wherein saidfirst limit position of said crank arm is displaced 120* from saidsecond limit position.
 4. Injection blow molding machine, as recited inclaim 1, wherein said first limit position of said crank arm isdisplaced 90* from said second limit position.
 5. Injection blow moldingmachine, as recited in claim 1, wherein said driving means comprises ahydraulic piston.
 6. Injection blow molding machine, as recited in claim1, wherein said crank arm rotates about said turret axis in unison witha second crank arm having at its outer end a first engagement means forengaging said turret.
 7. Injection blow molding machine, as recited inclaim 6, wherein said first engagement means comprises a radiallydisposed flag member and said second engagement means comprises aplurality of receiving slots for said flag member, said slots having anangular displacement therebetween corresponding to the angle betweensaid limit positions of said crank arm.
 8. Injection blow moldingmachine, as recited in claim 7, wherein said flag member is pivotallymounted on said second crank arm to permit rotation of said flag memberabout an axis perpendicular to the planar faces thereof into a positionwherein it does not engage said second engagement means.
 9. Injectionblow molding machine, as recited in claim 8, wherein said driving meanscomprises a hydraulic piston, and said crank arm limit positions aredisplaced 90* - 120*.
 10. Injection blow molding machine, as recited inclaim 9, wherein said crank arm and said linear link member are ofapproximately equal length.
 11. Injection blow molding machine, asrecited in claim 9, further including sequencing means for repeatedlyproducing the following sequence of events, a. turret moves toward andengages said indexing means, while movable mold halves move in unisontherewith to open said injection and blow molds, b. driving means movessaid crank arm to said second limit position, c. turret moves away fromand disengages said indexing means, while movable mold halves move inunison therewith to close said injection and blow molds, d. indexingmeans returns crank arm to said first limit position, e. plastic isinjected into said injection molds, compressed fluid is released intothe space surrounding said core rod set enclosed by said blow molds, andbottles are removed from one of said core rod sets not enclosed by saidinjection and blow molds.